Androgenesis-Based Doubled Haploidy: Past, Present, and Future Perspectives

Abstract

Androgenesis, which entails cell fate redirection within the microgametophyte, is employed widely for genetic gain in plant breeding programs. Moreover, androgenesis-responsive species provide tractable systems for studying cell cycle regulation, meiotic recombination, and apozygotic embryogenesis within plant cells. Past research on androgenesis has focused on protocol development with emphasis on temperature pretreatments of donor plants or floral buds, and tissue culture optimization because androgenesis has different nutritional requirements than somatic embryogenesis. Protocol development for new species and genotypes within responsive species continues to the present day, but slowly. There is more focus presently on understanding how protocols work in order to extend them to additional genotypes and species. Transcriptomic and epigenetic analyses of induced microspores have revealed some of the cellular and molecular responses required for or associated with androgenesis. For example, microRNAs appear to regulate early microspore responses to external stimuli; trichostatin-A, a histone deacetylase inhibitor, acts as an epigenetic additive; ά-phytosulfokine, a five amino acid sulfated peptide, promotes androgenesis in some species. Additionally, present work on gene transfer and genome editing in microspores suggest that future endeavors will likely incorporate greater precision with the genetic composition of microspores used in doubled haploid breeding, thus likely to realize a greater impact on crop improvement. In this review, we evaluate basic breeding applications of androgenesis, explore the utility of genomics and gene editing technologies for protocol development, and provide considerations to overcome genotype specificity and morphogenic recalcitrance in non-model plant systems.

Establishment of a dmp based maternal haploid induction system for polyploid Brassica napus and Nicotiana tabacum

“…Alternatively, homozygous lines can also be obtained in a single generation using doubled haploid (DH) technology (Jacquier et al, 2020). Haploid embryos can be induced in vitro from cells of the male or female gametophyte or in vivo in seeds by interspecific crosses or by intraspecific crosses with haploid inducer lines (Kalinowska et al, 2019; Lv et al, 2020; Wang et al, 2021a; Hale et al, 2022). Efficient in vitro haploid induction (HI) systems have been developed for a number of dicot crops, among which are the allotetraploid crops Brassica napus and Nicotiana tabacum .…”

Androgenesis in indica rice: A comparative competency in development of doubled haploids

“…The foremost benefit of anther culture is regaining of genetically fixed doubled haploid (DH) plants. The efficacy of this technique is determined by the productivity of haploid plant regeneration from the anther derived microspores and subsequently conversion of these haploids to doubled haploids through genome doubling [ 9 ]. The duration for producing DH lines requires a single generation while the conventional breeding needs 7–8 generations of self-pollination to achieve the pure lines.…”

Genetic Augmentation of Legume Crops Using Genomic Resources and Genotyping Platforms for Nutritional Food Security

“…However, sometimes, similar genotypes may also release genetic variation during recombination [ 45 ]. For example, bi-parental populations, such as RIL, NIL, and MAGIC, have been developed for marker–trait analysis in chickpea [ 46 , 47 ]. Similarly, RIL mapping populations have been developed in groundnut for the identification of marker–trait analysis [ 4 ].…”